Re: [Dorset] Cannot print to network lpd: after CUPS upgrade
Hi Ralph On 26/09/15 10:23, Ralph Corderoy wrote: Hi Tim, Yes I could but as I've found a work-around I think I need to move on to some of the other new CUPS problems this release has thrown up. I found mention of kernel TCP changes causing problems with Edimax Ethernet/Centronics interfaces, amongst other makes. The workaround was to set sysctl(8)'s net.ipv4.tcp_frto to 0. Without it, data was sent very slowly to the printer and it would give up waiting. Seems it was acknowledged as a kernel bug. Ralph to the rescue yet again :) That was it. Really strange that this bug was reported in Ubuntu back in '08 but I've only just seen it here. Cheers Tim -- Next meeting: Bournemouth, Tuesday, 2015-10-06 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Cannot print to network lpd: after CUPS upgrade
Hi Tim, > Yes I could but as I've found a work-around I think I need to move on > to some of the other new CUPS problems this release has thrown up. I found mention of kernel TCP changes causing problems with Edimax Ethernet/Centronics interfaces, amongst other makes. The workaround was to set sysctl(8)'s net.ipv4.tcp_frto to 0. Without it, data was sent very slowly to the printer and it would give up waiting. Seems it was acknowledged as a kernel bug. Cheers, Ralph. -- Next meeting: Bournemouth, Tuesday, 2015-10-06 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Cannot print to network lpd: after CUPS upgrade
Hi Ralph On 25/09/15 15:38, Ralph Corderoy wrote: Hi Tim, After the upgrade, print spooling to an old HP Laserjet 6P through an Edimax ethernet-Centronics print server stalls (lpd://printer:lpt1). That a Pi still on CUPS 1.5.3 is odd, as if it isn't the Jessie upgrade that's broken things. Yes, that really surprised me and I'm all too aware that device failures do coincide with upgrades leading to a wild goose chase. Having systematically swapped out the Edimax, its PSU, network cable and ethernet switch port I fully expected it to work. I'm wondering if it's an Avahi-related issue, but I'd already upgraded other machines on the network. Not sure if Avahi daemon was running on Wheezy. LPD is an old and simple protocol IIRC. Have you tried capturing the network packets from the sending machine with tcpdump(8) or Wireshark, and looking at them in the latter, not necessarily on the same machine? It might show which end speaks last. A small print job would lessen the noise from the print out itself, and you can increase the size if small ones work OK. Yes I could but as I've found a work-around I think I need to move on to some of the other new CUPS problems this release has thrown up. Cheers Tim -- Next meeting: Bournemouth, Tuesday, 2015-10-06 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Cannot print to network lpd: after CUPS upgrade
Hi Tim, > After the upgrade, print spooling to an old HP Laserjet 6P through an > Edimax ethernet-Centronics print server stalls (lpd://printer:lpt1). That a Pi still on CUPS 1.5.3 is odd, as if it isn't the Jessie upgrade that's broken things. LPD is an old and simple protocol IIRC. Have you tried capturing the network packets from the sending machine with tcpdump(8) or Wireshark, and looking at them in the latter, not necessarily on the same machine? It might show which end speaks last. A small print job would lessen the noise from the print out itself, and you can increase the size if small ones work OK. Cheers, Ralph. -- Next meeting: Bournemouth, Tuesday, 2015-10-06 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
[Dorset] Cannot print to network lpd: after CUPS upgrade
Hi Recently upgraded a machine from Debian Wheezy (CUPS 1.5.3) to Jessie (CUPS 1.7.5). After the upgrade, print spooling to an old HP Laserjet 6P through an Edimax ethernet-Centronics print server stalls (lpd://printer:lpt1). This setup has been working previously for 10+ years. I can print to other networked lpd printers. Tried a Raspberry Pi, still on CUPS 1.5.3 - that also stalls which really surprised me. Swapping Edimaxes doesn't help. Looked at the differences in the source for lpd driver between 1.5.3 and 1.7.5 - can't see anything obvious. For now I've hooked up a USB-Centronics print server cable, but I'm really intrigued as to what the incompatibility is. Logs (on logging level debug) didn't show up anything obvious. Cheers Tim -- Next meeting: Bournemouth, Tuesday, 2015-10-06 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
